Octopus Australia Acquires 4.8GWh Battery Storage Project in New South Wales

Why It Matters

With 75% of Australia’s coal capacity slated for retirement within a decade, large‑scale storage is essential for grid reliability and a clean‑energy transition, making Octopus’s acquisitions a pivotal step toward a resilient, low‑carbon power system.

Key Takeaways

• 1.2 GW/4.8 GWh Hanworth BESS becomes Australia's largest planned battery
• Project will supply over 500,000 homes during peak evenings
• Acquisition expands Octopus's renewable portfolio across NSW and Queensland
• Supports replacement of retiring coal plants with firm, low‑emission power
• Institutional investors back project, signaling confidence in large‑scale storage

Pulse Analysis

Australia’s power landscape is at a tipping point as coal‑fired generators near the end of their economic life. The International Energy Agency warns that flexible, fast‑responding assets will be required to balance the surge of variable renewables. Octopus Australia’s purchase of the Hanworth battery directly addresses this gap, offering 4.8 GWh of dispatchable energy that can be called upon during evening peaks, a period traditionally dominated by fossil‑fuel generation. By tying the storage to Transgrid’s Bannaby Terminal, the project integrates seamlessly into the National Electricity Market, providing a reliable bridge for large‑scale renewable contracts.

The technical scale of Hanworth sets a new benchmark for the nation. At 1.2 GW of power capacity, it eclipses the 760 MW Eraring BESS and the 850 MW Waratah Super Battery, while its 4.8 GWh energy rating translates to enough electricity to run over 500,000 households for several hours. This depth of storage enables time‑shifting of solar and wind output, smoothing intermittency and reducing reliance on expensive peaking generators. Moreover, the simultaneous acquisition of the Dunmore solar‑plus‑storage hybrid in Queensland demonstrates Octopus’s commitment to diversified, geographically dispersed assets that can balance supply across multiple regions.

Strategically, Octopus’s 100 % ownership model gives it full operational control, allowing the firm to lock in stable pricing for corporate off‑takers and hedge against wholesale market volatility. The backing of institutional investors such as the Clean Energy Finance Corporation, APG, Rest and Hostplus underscores confidence in the financial viability of large‑scale battery projects. As Australia phases out coal, the combined solar‑battery portfolio positions Octopus as a key player in delivering low‑carbon, firm power, while setting a template for future renewable‑plus‑storage developments across the Asia‑Pacific region.

Octopus Australia acquires 4.8GWh battery storage project in New South Wales

By George Heynes · February 5, 2026

Octopus Australia has announced plans to develop what it claims is Australia’s “largest planned battery energy storage system (BESS)” in New South Wales.

The company has acquired the proposed 1.2 GW / 4.8 GWh Hanworth Battery Energy Storage System near Bannaby, west of Bowral in New South Wales, which will become the largest planned battery project in Australia, the company said.

Indeed, once completed, the battery storage project will be larger than Origin Energy’s 760 MW / 3,160 MWh Eraring BESS in New South Wales, as well as Akaysha Energy’s 850 MW / 1,680 MWh Waratah Super Battery, which is currently operational.

The facility will connect to Transgrid’s Bannaby Terminal Station and provide sufficient storage capacity to power more than half a million homes during evening peak demand periods. It will connect to the National Electricity Market (NEM), which spans Australia’s eastern and southern states and territories.

The Hanworth battery project will support long‑term electricity supply contracts for large customers seeking firm renewable energy, facilitating low‑emissions power delivery at stable pricing. Hanworth was acquired from Australian energy developer Enervist. Enervist CEO Ross Warby described the Hanworth transaction as reflecting the strength of the company’s development portfolio and the significant investment completed to advance the project.

Octopus Australia has simultaneously acquired the Dunmore Solar Farm and Battery project in Queensland from Samsung C&T Renewable Energy Australia, marking the Korean company’s first renewable energy transaction in Australia. The hybrid solar‑plus‑storage development combines a 300 MW solar PV power plant with a 150 MW / 300 MWh battery storage system near Toowoomba, designed to capture surplus daytime solar generation and discharge during evening demand peaks. Samsung C&T Renewable Energy Australia managing director Jung Park highlighted the Dunmore project’s quality and strategic location as factors contributing to successful market demand.

Octopus Australia CEO Sam Reynolds emphasised the company’s commitment to replacing retiring coal‑fired generation with reliable renewable energy alternatives.

“Australia still needs new power stations to replace ageing coal plants. The difference is that today we can build them using a mix of solar, wind and batteries instead of smokestacks,” Reynolds said.

The investment strategy aligns with International Energy Agency assessments that power systems require flexible assets capable of rapid response and grid stabilisation to maintain reliability as clean generation increases. With approximately 75 % of Australia’s coal‑fired power stations scheduled for retirement within nine years, large‑scale replacement capacity has become a national infrastructure priority.

Technology integration and market positioning

Octopus Australia’s approach integrates multiple renewable energy technologies within a single portfolio structure, allowing energy shifting across geographic locations and temporal demand patterns. The company maintains 100 % ownership of portfolio assets, providing operational flexibility to match supply with demand without commercial constraints that affect multi‑owner project structures. Octopus Australia said its integrated model enables the company to supply customers with predictable power while reducing exposure to volatility in wholesale electricity prices.

The strategy has attracted investment from major institutional investors, including the Clean Energy Finance Corporation, European pension fund APG and Australian superannuation funds Rest and Hostplus.

The Dunmore project acquisition builds upon Octopus Australia’s expanding Queensland presence, which includes multiple solar and battery developments across the state. The company has previously secured financial close on a 486 MWh DC‑coupled solar‑plus‑storage facility and acquired the 400 MWh Coleambally battery project in New South Wales.